Separating the skin from everything is vital, and here we’ve desaturated and intensified the face. In fact, we’ve removed much of the colour from the overall image, as it wasn’t a strong focal point to begin with.
Make a duplicate of the background layer, and use the Dodge tool over the eyes to bleach reflections. Using the Sponge tool, set to Desaturate, remove colour from the eyes. Duplicate the layer, set Brush tool to black, Soft Light blend mode, and 20% Opacity.
Paint under the cheekbones, around the nose and eyes to intensify shadows. Using the Levels adjustment, darken overall midtones. Duplicate layer again, and make a selection around the skin and then inverse the selection. Add a layer mask, and reduce the Saturation of the layer to -60.
Create a new blank layer and fill it with white. Set its blend mode to Color, and Opacity to 65%. Activate the selection made earlier and inverse once again to select skin. Add a layer mask to the white fill layer. The skin should look pale. To finish, darken the hair and background layer below using Curves.